Frederick h



No. 748,977. PATENTED-JAN. 5, 1904.

' F. H. NIBS.

RUBBER DAM CLAMP. APPLICATION FILED APR. 8.1903.

N0 MODEL.

WITNESSES:

- IINVENTOR n4: NORRIS PETERS tn. mow-Lame WASHXNGTON. o. c.

Patented January 5,-1904.

PATENT OFFICE.

FREDERICK H. NIES, OF NEW YORK, N. Y.

RUBBER-DAM CLAMP.

SPECIFICATION forming part of Letters Patent No. 748,977, dated January5, 1904.

Application filed April 8. 1903.

To cw'l whom it may concern:

Be it known that l, FREDERICK H. NIES, a citizen of the United States,residing in the borough of Brooklyn, county of Kings, and city and Stateof New York, have invented certain new and useful Improvement-s inRubber-Dam Clamps, of which the following is a specification.

This invention relates to clamping devices employed in dentistry forholding in place the rubber dam while treating a tooth or teeth, andparticularly to that species of this class of devices wherein the clampcomprises two lever-like jaws-hinged together or articulated in somemanner and provided with means for closing the jaw-heads about the toothadjacent to the dam.

The object of the present invention is in part to provide thepivotally-connected levers with pivoted jaw-plates which adjustthemselves to the tooth 01' teeth, in part to reversible jaw-platespivotally mounted on the jaws, and in part to means for closing the aws.

In the accompanying drawings,which illustrate embodiments of theinvention, Figure 1 is a perspective view of an instrument embodying allof the features of the invention.

Fig. 2 is an under side view of the same. Fig. 3 is a view similar toFig. 1, illustrating a form of the instrument wherein the jawplates areadjustable, but not reversible. Fig. etis an under side view of thesame. Fig. 5 is a view showing the jaw-plate adapted for clamping on asingle tooth. Fig. 6 is a fragmentary sectional view showing theconstruc tion at the fulcrum-joint or pivot.

Referring, primarily, to Figs. 1 and 2, 1 and 1 designate jaw-levers,which are pivoted or jointed at the fulcrum-point and adapted to turnabout a pivot-pin 2. These levers have a spring 3 of any kind betweenthem in front of the fulcrum to open the jaws 4. Back of the fulcrum thejaw 1 has a prolongation 5, which is screw-threaded, and on this screwis a conical thumb-nut 6, which when the nut is driven in' on the screwbears on a short arm 7 of the lever 1 and closes the jaws 4 together. Asthe lovers which carry the jaws swing radially about the fulcrum-pivotthey diverge, and the angle of diversion increases with the increase inthe size of the tooth or Serial No. 151,619. (No model.)

teeth to be grasped by the jaws, and hence in order that the jaws mayadjust themselves and maintain either parallelism or the proper angleregardless of the divergence of the levers the jaws 4 are provided eachwith a jawplate 8, which is pivotally attached to the jaw 4: at 9, aboutthe middle of the length of the jaw-plate, so that the latter may rockabout its pivot, and thus adjust itself to the teeth.

In the construction shown in Figs. 3 and 4 the jaw-plates 8 are notrotatable about their pivots, but simply rock thereon, only one edge ofthe plate having concave recesses 10 to fit about the teeth. In theconstruction of Figs. 1 and 2 the jaw-plate 8 may turn entirely around,so as to present either edge thereof to the teeth. This is advantageousfor several reasons. It permits the plate to adjust itself to the teeth,as before explained, and it also permits the two edges of the plate tobe shaped differently, so that two distinct forms or shapes are providedinstead of one. In Fig. 2 it will benoted that the plate has in one edgetwo concave recesses only, while in the other edge it has three smallerrecesses.

Thesejaw-plates will be made by preference of thin steel plate, and theconcave recesses 10 will be or may be of different sizesfor example, theouter one the larger, so as to fit a molar, and the inner one or onenearest the fulcrum the smaller to fit an adjacent bicuspid.

Fig. 5 shows an instrument adapted for clamping on a single tooththatis, the jawplates 8 in this form have each but one recess 10. Otherwisethis construction is the same in substance as that before described.

The levers or jaw-carriers are bent at y for convenience of insertingthe instrument into the mouth.

Having thus described my invention, I claim-- 1. An instrument for thepurpose specified, comprising two levers pivotally connected at thefulcrum, jaws on the said levers, a recessed jaw-plate pivotally mountedon the face of each jaw, at about the middle of the length of the plate,whereby it may adjust itself to the tooth clamped, and means for openingand closing said jaws.

2. An instrument for the purpose specified,

comprising two levers pivotall y connected at their fulcrum, jaws onsaid levers, a jawplate pivotally mounted at about the middle of itslength on each of said jaws, said jawplates having a plurality ofconcave recesses in their edges for embracing two or more adjacentteeth, and means for opening and closing said jaws.

3. An instrument for the purpose specified, comprising two leversconnected pivotally at their fulcrum, jaws on said levers, means foropening and closing said jaws, and jaw-plates 8, rotatably mounted onthe respective jaws, said plates each having recesses in both of its 15edges.

4. An instrument for the purpose specified, comprising the loversconnected at their fulcrum, one of said levers having a screwthreadedextension 5, and the other an arm 7, the conical not 6 on the extension5, and bearing on the arm 7, the jaws on the levers, and the spring foropening said jaws.

In witness whereof I have hereunto signed my name, this 6th day ofApril, 1903, in the presence of two subscribing witnesses.

FREDERICK H. NIES.

Witnesses:

PETER A. Boss, WILLIAM J. FIRTH.

